The present invention relates to magnetic disk drives, and more particularly to a magnetic disk drive having a load/unload mechanism for a magnetic head.
In recent years, the proliferation of personal computers bestowed with portability has been increasing and smaller-size and larger-capacity magnetic disk drives mounted in these computers have come to be most commonly used. In addition to these tendencies, the enhancement of recording capacity and the improvement of shock resistance are being demanded each year. During non-operating time, conventional drives have moved their magnetic heads to specially surface-treated areas at the inner circumferential portion of associated disks to prevent the heads from adhering to the disks. The application of a shock, however, has resulted in a collision between the disk and the head, thus damaging both the disk and the head, and adversely affecting the reliability of the drive.
The prevailing drives in recent years, therefore, incorporate a ramp mechanism for moving out the head from the disk. When the drive is not to be operated, the ramp mechanism moves out the head from the disk in order to avoid a disk-to-head collision and improve the life and reliability of the drive as a result.
Such a compact magnetic disk drive has come to encounter the problem of a failure due to the application of a shock. Accordingly, magnetic disk drives have increasingly adopted, as one means of enhancing anti-shock performance, a load/unload mechanism by which a slider with a magnetic head mounted thereon is unloaded from a magnetic disk when data is not to be read therefrom or written thereto. Among these magnetic disk drives, the ones employing a ramp load scheme are prevailing, and this scheme has the advantages that it can be realized without introducing significant modifications into a conventional magnetic disk drive, and that costs can be minimized. An example of such a magnetic disk drive of the ramp load scheme is described in Patent Reference 1 (Japanese Patent Laid-Open No. Hei 11-96707). Also, Patent Reference 2 (Japanese Patent Laid-Open No. 2000-76811) describes a ramp load mechanism that includes a ramp provided outside a magnetic disk, and a tab extending from the front end of a loading member which applies a load to a head, wherein the tab can be engaged with the ramp. This tab is disposed in offset form with respect to the central axis of a head support member and at the outer peripheral edge of the magnetic disk, over the head support member. Thus, since the ramp is miniaturized and since a suspension is structurally divided into the head support member and the loading member, the magnetic head can be loaded/unloaded without rolling the head support member or the magnetic head, even if a rolling moment occurs to the loading member.